package com.itheima;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.function.BiConsumer;

public class MapDemo {
    public static void main(String[] args) {
        test1();
    }

    public static void test3() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("王五", 200.0);
        map.put("李四", 300.0);
        map.put("赵六", 400.0);

//        map.forEach(new BiConsumer<String, Double>() {
//            @Override
//            public void accept(String key, Double aDouble) {
//                System.out.println(key+"---"+aDouble);
//            }
//        });
        map.forEach((key,value)-> System.out.println(key+"---"+value));
    }

    public static void test2() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("王五", 200.0);
        map.put("李四", 300.0);
        map.put("赵六", 400.0);

        Set<Map.Entry<String, Double>> entrySet = map.entrySet();
        for (Map.Entry<String, Double> entry : entrySet) {
            String key = entry.getKey();
            Double value = entry.getValue();
            System.out.println(key+"---"+value);
        }
    }

    public static void test1() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("王五", 200.0);
        map.put("李四", 300.0);
        map.put("赵六", 400.0);

        Set<String> keySet = map.keySet();
        for (String key : keySet) {
            Double value = map.get(key);
            System.out.println(key+"---"+value);
        }
    }

    public static void test0(String[] args) {
        Map<String,Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("王五", 200.0);
        map.put("李四", 300.0);
        map.put("赵六", 400.0);
        map.put("李四", 500.0);
        System.out.println(map);

        map.remove("张三");
        System.out.println(map);
//        map.clear();
//        System.out.println(map);
        boolean b1 = map.containsKey("李四");
        System.out.println("b1="+b1);
        boolean b2 = map.containsValue(200.0);
        System.out.println("b2="+b2);

        boolean empty = map.isEmpty();
        System.out.println("empty="+empty);
        int size = map.size();
        System.out.println("size="+size);

    }
}
